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Rel, Math, Ratio, Channel Average, dB
Model 2701 User’s Manual
“Pressing REL” using rel commands
When the front panel REL key is pressed, the displayed reading is used as the rel value.
Subsequent readings are then the result of the actual input value and the rel value.
The :REFerence:ACQuire and :REFerence:STATe ON commands (in that order) can be
used to “press” the REL key. For example, the following command sequence is the
equivalent of pressing the REL key while on the DCV function:
VOLT:REF:ACQ
' Acquire reading as rel value.
VOLT:REF:STAT ON
' Enable rel.
Setting rel values
The :REFerence <n> command specifies the rel value for the specified function, while the
:ACQuire command uses the input signal as the rel value. The :ACQuire command is
typically used to zero the display. For example, if the instrument is displaying a 1µV
offset, sending :ACQuire and enabling rel (STATe ON) zeroes the display.
The ACQuire command is only functional if the instrument is on the specified function.
For example. If the instrument is on the DCV function, the only valid acquire command is
VOLT:DC:REF:ACQ. Also, if the instrument is overflowed (“OVERFLOW”) or a read-
ing has not been triggered (“------”), an execution error (-200) occurs when :ACQuire is
sent.
The :REFerence <n> command is coupled to the ACQuire command. When a rel value is
set using :REFerence <n>, the :REFerence? query command returns the programmed
value. When rel is set using :ACQuire, the :REFerence? query command returns the
acquired rel value.
Rel programming examples
Example #1 — The following command sequence zeroes the display for DCV.
NOTE
The following example can be run from the KE2700 Instrument Driver using the
example named “Relative1” in Table G-1 of Appendix G.
FUNC 'VOLT'
' Select DCV.
VOLT:REF:ACQ
' Use input level as rel value for DCV.
VOLT:REF:STAT ON
' Enable rel.
Example #2 — The following command sequence configures channel 101 of the
Model 7700 to enable rel and use a 1V rel value when it is scanned.
NOTE
The following example can be run from the KE2700 Instrument Driver using the
example named “Relative2” in Table G-1 of Appendix G.
FUNC 'VOLT',(@101)
' Select DCV for channel 101.
VOLT:REF 1,(@101)
' Set 1V rel value.
VOLT:REF:STAT ON,(@101)
' Enable rel.
2701-900-01.book Page 6 Wednesday, August 3, 2011 9:43 AM
Summary of Contents for 2701
Page 344: ...12 CommonCommands 2701 900 01 book Page 1 Wednesday August 3 2011 9 43 AM...
Page 366: ...15 SCPIReferenceTables 2701 900 01 book Page 1 Wednesday August 3 2011 9 43 AM...
Page 393: ...A Specifications 2701 900 01 book Page 1 Wednesday August 3 2011 9 43 AM...
Page 399: ...B Model7700ConnectionGuide 2701 900 01 book Page 1 Wednesday August 3 2011 9 43 AM...
Page 410: ...C StatusandErrorMessages 2701 900 01 book Page 1 Wednesday August 3 2011 9 43 AM...
Page 417: ...D SignalProcessing SequenceandDataFlow 2701 900 01 book Page 1 Wednesday August 3 2011 9 43 AM...
Page 430: ...E MeasurementConsiderations 2701 900 01 book Page 1 Wednesday August 3 2011 9 43 AM...
Page 450: ...G KE2700InstrumentDriver Examples 2701 900 01 book Page 1 Wednesday August 3 2011 9 43 AM...